var n,m:byte;
    a:array [1..17,1..17] of longint;
    b:array [1..17] of boolean;
    max:longint;

procedure citeste;
  var f:text;
      i,j:byte;
  begin
    assign(f,'flip.in');
    reset(f);
    readln(f,n,m);
    for i:=1 to n do for j:=1 to m do read(f,a[i,j]);
    close(f);
  end;

procedure urmatorul;
  var i:byte;
  begin
    i:=1;
    while b[i] do begin
                    b[i]:=false;
                    i:=i+1;
                  end;
    b[i]:=true;
  end;

procedure verif;
  var i,j:byte;
      s,t:longint;
  begin
    t:=0;
    for i:=1 to n do begin
                       s:=0;
                       for j:=1 to m do if b[j] then s:=s+a[i,j]
                                                else s:=s-a[i,j];
                       if s<0 then t:=t-s
                              else t:=t+s;
                     end;
    if t>max then max:=t;
  end;

procedure calc;
  var x,i:longint;
  begin
    x:=1;
    for i:=1 to 17 do b[i]:=false;
    for i:=1 to m do x:=x*2;
    for i:=1 to x do begin
                       verif;
                       urmatorul;
                     end;
  end;

procedure afiseaza;
  var f:text;
  begin
    assign(f,'flip.out');
    rewrite(f);
    write(f,max);
    close(f);
  end;

begin
   citeste;
   calc;
   afiseaza;
end.